Writing instrument



Aug. 25, 1964 M. D. LEVY WRITING INSTRUMENT Filed July 2e, 1961 6/ l 3g @Z 57 4/ ZV-/ 56 4Z I l M 45 f/ gtk; 5/ 5/ 4 n /a 29 i /9 23 35 `\T. 2, 34 27 22 /5 25 4 I 20 90 l26 l /7 I 2/ 24 i *v INVENTOR,

MOQIQA- D. Levy ATTORNEYS United States Patent() 3,145,412 WRITING INSTRUMENT Morris D. Levy, Teaneck, NJ., assigner to David Kahn, Inc., North Bergen, NJ., a corporation of New Jersey Filed July 26, 1961, Ser. No. 126,917 16 Claims. (Cl. 15-569) The present invention relates to a writing instrument, and more particularly to the type known as a marking pen, wherein the writing tip is constituted by an absorbent applicator.

More specifically, the writing instrument of the pres* ent invention is directed to a marking pen which includes a reservoir for the writing fluid, and valve means for controlling the flow of the fluid from the reservoir to the writing tip.

In the prior art, as exemplified by Marsh Patent No. 1,857,467 and Brigham Patent No. 2,250,444, it has been proposed to make marking pens of the general character described above wherein the valve means is constituted by a tapered valve seat and a tapered valve plug biased against .said valve seat by means of a spring. In these prior art constructions, the valve plug has been a solid rigid member by virtue of which the valve seat and surface of the valve plug must be complementary in shape and accurately machined in order to provide a valve which will not leak. However, when attempting to make such valve means out of plastic, by injection molding the parts, it has been found that because of the problems involved in plastic molding, a secure seal cannot be obtained. In addition, the prior art is deficient in providing means for readily refilling or changing the ink reservoirs.

These and other problems in the prior art have been overcome by the present invention. According to one aspect of the present invention, there is provided a pen section assembly which comprises a pen holder having a bore therethrough and valve means in said bore. The valve means comprises a valve seat and a valve member slidably mounted in said bore, said valve member having an upwardly flaring resilient valve body which is resiliently biased toward said valve seat. By providing a resilient valve body itis not necessary that the abutting surfaces of the valve body and the valve seat perfectly mate, Since the variations in the abutting surfaces can be accommodated by the resilient nature of the valve body.

According to the preferred embodiment of the present invention, the valve body is hollow and is defined by a relatively thin resilient wall so that the valve body can readily conform to the surface of the valve seat and thereby effect a good seal.

According to the another aspect of the present invention, the writing fluid reservoir is dened by the barrel itself with the barrel and the pen'section assembly being so designed that when the fluid supply has to be replaced, the barrel is removed and is replaced by a new barrel containing additional writing fluid. This result is obtained by providing a replaceable barrel with a pierceable partition near the forward end thereof and providing the pen section assembly with a piercing extension at the rear thereof so that when the barrel is screwed onto the pen section or otherwise secured thereto, the piercing extension of the pen section assembly pierces the partition in the barrel to provide a communication between the reservoir and the bore of the pen section assembly.

Accordingto another aspect of the invention, the writing instrument is provided with a cap which is provided with a blind bore defining a chamber for receiving the writing tip so that when the cap is secured to the pen the writing tip is sealed within the chamber to prevent loss of writing fluid from the tip when the pen is not in use.

'3,145,412 Patented Aug. 25, 1964 ICC These and other aspects of the invention will be readily apparent from the followingdescription, taken in conjunction with the accompanying drawings, in which;

FIG. l is an elevation of the writing instrument of the present invention, with parts thereof being shown in section.

FIG. 2 is a fragmentary, longitudinal cross section of the writing instrument of FIG. l, showing particularly the structure of the lower portion of the pen.

FIG. 3 is a fragmentary, longitudinal section of the writing instrument of FIG. 1, showing the position of the parts immediately before the barrel is firmly secured to the pen section assembly.

FIG. 4 is a perspective View of the Valve member.

FIG. 5 shows a fragmentary exploded view of the fore ward end of the pen section and the bushing which holds the valve in place, the pen section beingshown in section.

The writinginstrument of the present invention comprises a pen 10 and a cap 11, the pen and the cap being releasably secured to each other by means of external threads 12 on the pen'and internal threads 13 on the cap. The cap may have fastened thereto a clip 14.

In the following description and in the claims, the instrument will be considered as being held in a normal writing position, that is, with the writing tip facing down# wardly. Therefore, the words forward and downward will refer to a direction towardsthe tip, whereas the words rearward and upward 'will refer to the direction away from the writing tip.

The pen 10 includes a pen section assembly 15 and a barrel 16, the pen section assembly including a pen holder 17 of the conventional downwardly tapered shape. The pen holder is provided at the rear thereof with an externally threaded extension 18 of reduced diameter for fastening the pen section assembly into the barrel 16. By virtue of the reduced diameter of the threaded extension 1S, the pen 'holder 1'7 is provided with an annular abutment 19, the purpose of which will be later described.

The pen holder 17 has a vlongitudinal bore 20 therethrough, said bore being defined by a lower bore 21 and `an upper bore 22 of greater diameter so that the intersection or junction of the bores forms an internal annular shoulder 23, which defines a valve seat. In the preferred construction, as shown in the'drawing, the valve seat 23 is downwardly tapered, or stated differently, the valve seat 23 is upwardly flared. `Slidably mounted in the forward portion of bore'21 is a writing tip 24, whichis made of an absorbent material such as felt. The forward extremity of the writing tip is preferably pointed, being in' the shape of a cone as shown at 25, although it is apparent that the tip may be of any conventional shape, such as chisel-shaped (not shown), the edge being formed by a single bevel or two opposed bevels. v

A valve member 25 is also slidably mounted in bore 20 rearward of the writing tip 24. The valve member is constituted by a valve stem 27 having mounted thereon intermediate its ends a valve body or plug 28, said valve plug being upwardly flared, or stated differently, downwardly tapered. The valve plug is made of resilient material.' According to the preferred construction, as illustrated in the drawing, the valve plug 28 ispreferably constituted by a relatively thin generally conical or funnelshaped wall 29. The lower end of wall 29 is secured to the valve stem, while the upper end of wall 29 flares away and is free of said valve stem, so that it may be said that the valve plug 28 is a hollow valve plug.

The valve stem 27 is constituted by a lower portion 30, an intermediate portion 31 of lesser diameter, and a rear portion 52 of still lesser diameter, the junction of the lower portion 30 and intermediate portion 31 defining an annular shoulder or seat 33 for downwardly tapered helical spring 34.

The valve member is maintained in the pen holder 17 by means of hollow bushing 35 having an axial bore 36 therethrough. The bushing 35 includes a rear tubular piercing extension 37 of lesser diameter than the bushing 35. The tubular extension 37 has a bore 38 therethrough coaxial and communicating with bore 36 of the bushing 35. The rearward extremity 39 of the tubular extension 37 is beveled, that is, cut on an incline to provide a relatively sharp piercing edge 40.

The forward portion of bushing 35 defines a seat 41 for the rear and wider end of valve spring 34. The bushing 35 is provided with an annular groove 42 around the periphery thereof near the lower end and the interior of the pen holder 17 in bore 22 is provided with inwardly extending projection means such as rib 43, which is received within groove 42 to secure the bushing 35 in pen holder 17.

The pen section assembly is assembled by inserting the forward end of valve stem 27 through the rear of pen holder 17. The spring 34 is then positioned around the rear of the valve stem and the bushing 35 is inserted into bore 22 until the rib 43 is received within groove 42 to maintain the bushing 35 and the valve member 26 in position. When the valve member is fixed in pen holder 17, the writing tip 24 is inserted from the forward extremity of bore 21 until the rear 44 of the writing tip abuts the forward face 45 of the valve member 26.

According to the preferred construction of the present invention, the barrel 16 defines a replaceable reservoir for the writing instrument, the interior of said barrel being hollow and defining a chamber 46 for holding the writing fluid. The writing fluid is normally sealed within chamber 46 by means of a sealing bushing 47 force-fitted or otherwise secured within the barrel 16 near the forward end.

The sealing bushing 47 is pierceable and denes a piercable closure for the writing iiuid reservoir constiuted by the hollow barrel 16. The pierceable sealing bushing 47 comprises a head portion 48 and a rear portion 49, the head portion having an annular guide dened by a central axial bore 50, said bore having a diameter substantially equal to the external diameter of the tubular piercing extension 37, so that the piercing extension can be received within bore 50 in a substantially fluid-tight manner.

The rear portion 49 of the pierceable bushing 47 has an axial bore 51 coaxial with and of greater diameter than bore 50, bores 50 and 51 being separated by an openable partition 52 across the bore 50 on the head portion 48.

When the barrel 16 is to be secured to the pen section assembly 15, the forward part of the barrel is threaded onto the rear of the pen section assembly, the barrel 16 being provided at its forward end with internal threads 53 which engage the threads of the threaded extension 18 of the pen holder 17. As the barrel and the pen section assembly are threaded together, the piercing extension 37 is first received within the annular guide 50, as shown in FIG. 3. It is noted that piercing extension 37 is coaxial with bore 50. As the barrel is further screwed onto the pen section assembly, the piercing edge 40 cuts through the periphery of the openable partition 52, which partition is relatively thin, so that it will be cut through by the piercing edge, until the partition is severed sufliciently to provide communication between the bore 50 and bore 51. As is apparent from FIG. 2, the openable partition 52 is not completely severed from the head portion 48, but remains secured thereto. The diameter of bore 51 is suiciently large to accommodate therein the piercing extension as well as the partition 52. Once the partition 52 has been opened, there is free communication between the reservoir chamber 46, bore 51, bore l), bore 36 and bore 22. At this time, the writing uid can, therefore, readily iiow from the reservoir into bore 22, where its ow is halted by valve plug 23 being seated against valve seat 23.

The barrel 16 is screwed onto the pen section assembly until the forward edge 53A of the barrel abuts the annular abutment 19 on the pen holder whereby the barrel and pen holder form a fluid tight engagement in order to prevent the ink from leaking out of the barrel to the exterior of the pen.

Spring 34 normally biases the valve member downwardly so that the valve plug is biased toward and against the valve seat 23.

ln order to start the ow of the writing fluid from the bore 22 into bore 21 and from there through the absorbent writing tip 24, it is necessary to apply a rearward pressure against the writing tip 24. This rearward pressure is transmitted to the valve member 26 by virtue of the abutting surfaces 44 of the writing tip and 45 of the valve stem. The valve stem, together with the valve plug, therefore, moves rearwardly to unseat the valve plug from the valve seat 23, and thereby permit the fluid to flow to the writing tip.

In marking pens of the type herein described, the writing tiuid or ink is relatively fluid and it is usually not desirable to have a continuous flow of ink from the reservoir to the writing tip. The valve means herein described constitute a means for intermittently feeding the ink from the reservoir to the writing tip.

Spring 34, which is a compression spring, is so selected that it will maintain the valve closed when the pen is used for normal writing or marking. Since the ink can be applied rather freely by means of the absorbent writing tip 24, it is not necessary to use much pressure when writing with the marking pen, and therefore, the valve normally stays closed during the writing operation. As soon as it is apparent to the user that the absorbent writing tip is beginning to run dry, additional rearward pressure is applied to the writing tip, thereby urging the valve to the open position and permitting additional writing uid to flow to the writing tip, whereupon the additional pressure is released, and normal writing can continue.

When the pen is not being used for writing, the point is covered by means of cap 11, the cap, at its forward or closed end being provided with a blind bore for receiving the writing tip and preventing evaporation of the ink therefrom. In the illustrated embodiment, this blind bore is provided by an inner cap or bushing 54 provided with a blind bore 55, the open end of which faces the open end of the cap. The inner cap 54 is also provided with an annular shoulder 56, which sealingly engages the forward extremity 57 of the pen holder so that when the pen is inserted within the cap, the writing tip is sealed within bore in a uid tight manner to prevent evaporation of the ink from the writing tip. The inner cap 54 is force-fitted within the cap 11. Preferably, the upper end of inner cap 54 is of reduced diameter to provide a space 58 which will accommodate the fastening means for the clip 14.

Referring again to bushing 35, this bushing is provided with a plurality of axially extending ribs 59. These ribs are positioned in spaced apart bands around the periphery of the bushing above the groove 42. These ribs 59 mate with utes 60 positioned around the interior of threaded extension 18 of the pen holder 17. Bushing 35 is also provided with a radial enlargement 61 which forms a shoulder for abutting the upper extremity or edge of threaded extension 18. When the bushing 35 is forced into extension 13, the ribs 59 and flutes 60 mate to prevent rotation of the bushing 35. The interaction between the ribs 59 and flutes 60 and the rib 43 and groove 42 serves to firmly secure the bushing 35 within the pen holder.

It will be observed, as shown in FIG. 2, that when the barrel is securely fastened to the pen section assembly, a uid tight connection between the pen holder and the barrel is obtained, not only by the abutment of edge 53A and abutment 19, but also by the abutment of the lower face of sealing bushing 47 with the upper face of bushing 35, this engagement also `u rging shoulder 61 against the upper edge of the lthreaded extension 18.

Bushing 47, bushing 35, valve member 26 and inner cap 54 are all preferably made from plastic material, the plastic material being most desirable is a plastic which is somewhat yielding in natura-such as nylon, a 'synthetic linear polyamide. Because of the yielding nature of such apl'asti'c, the abutment of Athe various parts as y described above serves to provide a fluid tight seal and prevent undesirable leakage of the writing fluid. The barrel and the pen holder may be m'ade from any desirable material, excellent results being obtained when they are made from a plastic such as cellulose acetobutyrate.

As shown in the drawing, valve member 26 is preferably rnade from one piece of material with the Valve body 28 being integral with the valve stem 27. The valve member can be made in this manner by injection molding of nylon or other appropriate plastic. By having the valve body or plug 28 constituted by relatively thin wall 29, it is possible to have the sealing surface of the valve substantially resilient, while the rest of the valve member, particularly the valve stem 27, is relatively stiff. In this way, the valve will mate properly with the valve seat 23, while the valve stem will not be distorted under the pressure of spring 34 and/ or the pressure of the writing tip when the valve is being opened. The thickness of the wall depends upon the material being used, it being necessary that the wall be suticiently thin to maintain its resilient or yielding nature, but be sufciently thick to maintain its position against the valve seat. In using nylon, it has been found that excellent results have been obtained when the thickness of the wall is of the order of one one-hundredths of an inch thick. By way of example, the wall may be between .010 and .012 inch thick.

In the preferred construction, the writing tip is not secured to the valve stem and is maintained within the forward portion of the pen holder merely by friction, with the writing tip and valve member being so positioned in the bore 26 that rearward pressure on the writing tip will force the valve plug away from the valve seat against the resilient force of spring means 34.

In the above description, the instrument of the present invention has been described as a writing instrument or marking pen. It is readily apparent that this terminology includes not only instruments which'are used for writing or marking in a normal sense, but also instruments which are used to apply iluid other than that which is used for writing or marking.

In the illustrated embodiment, all of the parts thereof are circular in cross section. It will be apparent that a cross sectional shape of some of the parts can be changed without departing from the spirit of the invention.

By way of example, bore 21 and the absorbent writing tip 24 may be rectangular (not shown) in shape. It will be appreciated that in the illustrated embodiment, wall 2.9, whichis annular in shape and defines the sealing surface of the valve plug is complementary in shape to the valve seat 23. Nevertheless, it is readily apparent that because of the resilient nature of wall 29, these parts do not have to be complementary in shape to effect a good seal.

It is noted that in the illustrated embodiment, the rear portion 32 of valve stem 27 extends into the tubular piercing extension 37. This serves to centralize the valve stem and, therefore, the valve to obtain positive seating. Additionally, the presence of the rear portion 32 within the tubular extension serves to control the ilow of ink through the tubular extension.

It is noted that when the valve is in the closed position, as shown in FIG. 2, the rear extremity of the rear poirtion 32 is positioned slightly below the lowest portion of the bevel on the tubular extension 37 so that the valve stern will not interfere with the piercing of the diaphragm. Preferably the rear portion 32 of the valve stem terminates just below the bevel when the valve is in the closed position and extends above the bevel when the valve is in theopen position so that the reciprocating movement of the valve stem assists in the ilow of ink from the reservoir into the tubular extension.

I claim:

l. A pen section assembly comprising a pen holder having a longitudinal bore therethrough, `a writing 'tip slidably mounted in the forward end of said bore, a valve seat in said bore, a Valve member slidably mounted in said bore, said valve member having a hollow resilient valve plug fashioned of one piece of material and comprising an outwardly flaring relatively thin annular wall for engaging said seat to close said bore, and resilient means biasing said valve plug towards said valve seat, said writing tip and valve member being so positioned in said bore that rearward pressure on said writing tip will force said valve plug away from said seat against the force of said resilient means.

2. A pen section assembly according to claim l, wherein said hollow resilient valve plug is flared upwardly.

3. A pen section assembly according to claim l, wherein said resilient valve plug wherein said valve member comprises a valve stem and said valve plug is integral with said stem.

4. A pen section assembly according to claim 3, wherein said valve seat is defined by an internal, annular upwardly haring shoulder.

5. A pen section assembly according to claim 3, including a rear tubular extension of lesser diameter than said pen holder, the rearrnost extremity of said extension defining a piercing tip.

6. A pen section Vassembly comprising a pen holderhaving a longitudinal bore therethrough, an absorbent writing tip slidably mounted in the forward end of said bore, an annular valve seat in said bore, a. valve member slidably mounted in said bore, said valve member cornprising a valve stem, a resilient Valve plug integral with said stem, said valve plug being dened by an upwardly flaring relatively thin annular wall about said valve stem, a spring seat on said valve stem, a spring having one end seated against said spring seat, a hollow bushing iixed within the bore of said pen holder near the upper end thereof, the upper end of said spring being seated against the lower end of said bushing whereby said spring biases said valve plug towards said valve seat, said writing tip and valve member being so positioned in said bore that rearward pressure on said writing tip will force said valve plug away from said valve seat against the force of said spring.

7. A writing instrument according to claim 6, wherein said bushing has a tubular rear extension terminating in a beveled end defining a piercing tip.

8. A writing instrument comprising a writing fluid reservoir secured to a pen section assembly, said pen section assembly comprising a pen holder having a longitudinal bore therethrough, a writing tip slidably mounted in the forward end of said bore, a valve seat in said bore, a valve member slidably mounted in said bore, said valve member having a hollow resilient valve plug fashioned of one piece of material and comprising an outwardly flaring relatively thin annular wall for engaging said seat to close said bore, and resilient means biasing said valve plug towards said Valve seat, said writing tip and valve member being so positioned in said bore that rearward pressure on said writing tip will force said valve plug away from said seat against the force of said resilient means.

9. A writing instrument according to claim 8, wherein said reservoir is constituted by a replaceable barrel removably secured to said pen section assembly, and wherein said wall flares upwardly.

l0. A writing instrument according to claim 9, wherein said valve seat is defined by an internal annular upwardly aring shoulder.

ll. A writing instrument according to claim 9, wherein said pen section assembly includes a rear tubular extension of lesser diameter than said pen holder, said rear tubular extension being removably received within the forward end of said barrel to provide communication between the reservoir and the pen section assembly.

12. A writing instrument according to claim 11, wherein said rear tubular extension defines a piercing tip at the rearmost extremity thereof, said piercing tip piercing an openable partition in said barrel.

13. A writing instrument according to claim 8, including a cap for removably enclosing the forward portion of the pen section assembly, said cap having at its forward end a blind bore opening rearwardly for receiving the Writing tip, an annular shoulder near the opening of said blind bore for sealingly engaging the forward extremity of thepen holder whereby the writing tip is sealed within the blind bore.

14. A pen section assembly according to claim 1, wherein said valve member is made of nylon.

15. A pen section assembly according to claim 6, wherein said valve member is made of nylon.

16. A pen section assembly according to claim l5, wherein said annular wall is of the order of one-hundredths of an inch thick.

References Cited in the le of this patent UNITED STATES PATENTS 616,990 Tallmadge Jan. 3, 1899 1,857,467 Marsh May 10, 1932 2,466,785 Schreyer Apr. 12, 1949 2,598,629 Whyte May 27, 1952 2,623,227 Moonert Dec. 30, 1952 2,745,631 Shellman May 15, 1956 2,821,356 Rand Jan. 28, 1958 2,866,994 Neely Jan. 6, 1959 3,028,139 Mastis Apr. 3, 1962 D STATES PATENT OFFICE UNITE CERTIFICATE 0F CORRECTIGN Patent No 3 ,145 ,412 August Z5 1964 I Morris D. Levy s in the abo-ve numbered patthat error appear hould read as that the Said Letters Patent S ereby certified It is h orrection and ent requiring c corrected below "wherein said Co1umn 6 lines Z1 and 22 strike out resilient valve p1ug" line 4 strike out "A writing instru'.-

' d A pen section assembIy column one oned insert instea -hundredths" rea ment" an d 5 for "one 8, Iines 4 an hundredths Signed and sea led this ist day of June 1965.

(SEAL) Attest:

EDWARD J BRENNER Commissioner of Patents ERNEST W. SWIDER Attest'mg Officer 

1. A PEN SECTION ASSEMBLY COMPRISING A PEN HOLDER HAVING A LONGITUDINAL BORE THERETHROUGH, A WRITING TIP SLIDABLE MOUNTED IN THE FORWARD END OF SAID BORE, A VALVE SEAT IN SAID BORE, A VALVE MEMBER SLIDABLE MOUNTED IN SAID BORE, SAID VALVE MEMBER HAVING A HOLLOW RESILIENT VALVE PLUG FASHIONED OF ONE PIECE OF MATERIAL AND COMPRISING AN OUTWARDLY FLARING RELATIVELY THIN ANNULAR WALL FOR ENGAGING SAID SEAT TO CLOSE SAID BORE, AND RESILIENT MEANS BIASING SAID VALVE PLUG TOWARDS SAID VALVE SEAT, SAID WRITING TIP AND VALVE MEMBER BEING SO POSITIONED IN SAID BORE THAN REARWARD PRESSURE ON SAID WRITING TIP WILL FORCE SAID VALVE PLUG AWAY FROM SAID SEAT AGAINST THE FORCE OF SAID RESILIENT MEANS. 